US20110286187A1 - Unibody Latch for Plug-In Units - Google Patents

Abstract

A latch for use with a plug-in unit may comprise a head, a rigid body, a pin, and a lever. The head may be configured to retain the plug-in unit within a chassis associated with a rack system. The rigid body may extend from the head and be configured to interface with a user's fingers. The pin may extend transversely from both sides of the head into a case associated with the plug-in unit and be configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers. The lever may extend from the rigid body and include a detent configured to engage the chassis. The detent may be configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the chassis. The lever may be operable to release the detent from the chassis. The head, the rigid body, the lever, and the detent are manufactured as a single unitary body.

Description

TECHNICAL FIELD OF THE INVENTION
• The present invention relates generally to modular components for a telecommunications network, and more particularly to a unibody latch for plug-in units.
BACKGROUND
• Telecommunications systems, cable television systems, and data communication networks use optical networks to rapidly convey large amounts of information between remote points. In an optical network, information is conveyed in the form of optical signals through optical fibers. Optical fibers comprise thin strands of glass capable of transmitting the signals over long distances with very low loss. Optical networks provide higher capacity and reduced operating costs compared to traditional technologies. Fiber-optic networks may include a system of multiple network components, including switches, routers, converters, modulators, demodulators, etc.
• A communications network may include one or more rack systems. A rack system includes two or more vertical posts providing a frame for mounting various components of the network system (e.g., a rack server). The rack system provides a plurality of mounting slots known as bays configured to hold a rack server and/or other network components. The rack system may allow multiple components to be stacked vertically, providing a relatively small footprint and simplifying cable connections between various components.
• A network system component may include multiple electronic components housed in a chassis. A chassis may be a rectangular box or another housing that provides electronic and/or physical connections for the internal components disposed therein. For example, the chassis may include a motherboard, a midplane, a backplane, switches, routers, converters, modulators, demodulators, etc. In those systems, plug-in units (PIU) may be used to provide a variety of applications and functions. PIUs may be inserted into a chassis and coupled to a backplane or a midplane.
SUMMARY
• In accordance with a particular embodiment of the present invention, a latch for use with a plug-in unit may comprise a head, a rigid body, a pin, and a lever. The head may be configured to retain the plug-in unit within a chassis associated with a rack system. The rigid body may extend from the head and be configured to interface with a user's fingers. The pin may extend transversely from both sides of the head into a case associated with the plug-in unit and be configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers. The lever may extend from the rigid body and include a detent configured to engage the chassis. The detent may be configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the chassis. The lever may be operable to release the detent from the chassis. The head, the rigid body, the lever, and the detent are manufactured as a single unitary body.
• In accordance with another particular embodiment of the present invention, a case for a plug-in unit for use with a chassis mounted in a rack system may include a housing for the electronic components of the plug-in unit, a head, a rigid body, a pin, and a lever. The head may be configured to retain the plug-in unit within the chassis. The rigid body may extend from the head configured to interface with a user's fingers. The pin may extend transversely from both sides of the head into the housing and be configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers. The lever may extend from the rigid body and include a detent configured to engage the chassis. The detent may be configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the chassis. The lever may be operable to release the detent from the chassis. The head, the rigid body, the lever, and the detent may be manufactured as a single unitary body.
• In accordance with another particular embodiment of the present invention, a rack system for use with a communications network may include two or more vertical posts, a chassis, housing for the electronic components of the plug-in unit, a head, a rigid body, a pin, and a lever. The two or more vertical posts may define bays for a plurality of chassis. The chassis may be mounted to the two or more vertical posts and provide a shelf for a plug-in unit. The head may be configured to retain the plug-in unit within the chassis. The rigid body may extend from the head configured to interface with a user's fingers. The pin may extend transversely from both sides of the head into the housing and be configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers. The lever may extend from the rigid body and include a detent configured to engage the chassis. The detent may be configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the chassis. The lever may be operable to release the detent from the chassis. The head, the rigid body, the lever, and the detent may be manufactured as a single unitary body.
• The teachings of the present disclosure may provide a variety of benefits in comparison to known alternatives. For example, manufacturing the head, the rigid body, the lever, and the detent as a single unitary body may remove the need for spring-loaded latches, thereby reducing part count and potential failure modes. As another example, manufacturing the head, the rigid body, the lever, and the detent as a single unitary body may allow a single material to be used for manufacture (e.g., a filled plastic and/or other selected material). As another example, manufacturing the head, the rigid body, the lever, and the detent as a single unitary body may allow a single step for manufacturing (e.g., injection molding and/or stamping).
• In addition, a latch with the detent and the head at separate physical locations also separates the retention load from the locking mechanism. That separation may allow a relatively high retention force provided by the head in conjunction with a relatively low removal force required to release the detent and allow the removal of the plug-in unit. It will be understood that the various embodiments of the present invention may include some, all, or none of the enumerated technical advantages. In addition, other technical advantages of the present invention may be readily apparent to one skilled in the art from the figures, description and claims included herein.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 illustrates example components of a communication system including a plug-in unit incorporating teachings of the present disclosure;
• FIG. 2 illustrates an example plug-in unit partially removed from a chassis, in accordance with the teachings of the present disclosure;
• FIG. 3 illustrates a detailed view of the plug-in unit fromFIG. 2;
• FIGS. 4A and 4B show various views of an example latch for use with a plug-in unit, in accordance with teachings of the present disclosure; and
• FIGS. 5A-5C show details of various example latches for use with a plug-in unit, in accordance with teachings of the present disclosure.
DETAILED DESCRIPTION
• Preferred embodiments and their advantages are best understood by reference toFIGS. 1 through 5C, wherein like numbers are used to indicate like and corresponding parts. Modular communication systems may employ plug-in units (“PIUs”) to provide a variety of functionality. PIUs may reside in a chassis coupled to a backplane and/or a midplane.FIG. 1 illustrates arack system10.Rack system10 may include achassis12, one or more plug-inunits14, and arack structure18. Although not visible inFIG. 1,system10 may include an I/O panel16.
• Rack system10 may be used for a variety of applications. In some embodiments,rack system10 may house various components of a communications system.Chassis12 may provide a housing for a variety of components associated with a communications network.Chassis12 may be connected to rackstructure18 with associatedbrackets20.
• Plug-inunit14 may comprise any suitable hardware and/or software operable to provide functionality for the communications system, including any memory, processor, or other components. Plug-inunit14 may provide networking applications, such as telecommunications or data routing. Plug-inunit14 may comprise physical interfaces on the front side, the back side, or both to connect to other network components and send signals to and receive signals from such other network components. Other embodiments may comprise a plurality of plug-inunits14. In addition, in some systems, plug-inunits14 are allocated in pairs.
• Plug-inunits14 couple to a backplane (not visible inFIG. 1) inchassis12. The backplane may provide a variety of functions insystem10, such as providing electrical connectivity between components ofsystem10 and transmitting signals between these components. Plug-inunits14 may comprise any suitable connector to couple to the backplane.Rack system10 may also house any appropriate number of plug-inunits14 or other components ofrack system10. The backplane may further comprise one or more midplane connectors (MPCs) (not visible inFIG. 1). The MPCs may receive one or more signals from one or more plug-inunits14, and may also receive one or more signals from the backplane. The MPCs may be associated with the backplane in some embodiments, or be a separate component in other embodiments. In certain embodiments, signals from one or more plug-inunits14 are coupled through the backplane to one or more MPCs. The MPCs may provide electrical connectivity to the backplane and/or to other components of the network communication system.
• The communication system may further comprise one or more I/O panels16. I/O panels16 may provide a variety of functionality forsystem10. I/O panels16 may couple to one or more plug-inunits14 to send signals and/or receive signals from plug-inunits14. I/O panels16 may communicate with plug-inunits14 through a backplane and/or an MPC. I/O panels16 may also comprise a variety of connectors for transmitting one or more signals. For example, some I/O panels16 may comprise one or more DS1 or DS3 connections. Other I/O panels16 may comprise Ethernet connections, such as 10BASE-T, 100BASE-T, or 1000BASE-T. The type of I/O panel16 may be selected by a user to provide the connections that the user needs for his or her applications. The user may also select an I/O panel16 that provides a protected interface or one that provides an unprotected interface.
• FIG. 2 illustrates an example plug-inunit14 partially removed fromchassis12, in accordance with the teachings of the present disclosure. Plug-inunit14 may include an associatedcase22 and alatch40.Case22 andlatch40 may operate in conjunction to attachPIU14 tochassis12. While various components internal tochassis12 may provide electrical and/or physical connections for PIU14 (e.g., a backplane),case22 andlatch40 may provide a more robust physical retention forPIU14. The retention provided bycase22 andlatch40 may protect the various internal connectors (e.g., a backplane and/or a midplane) from forces acting onPIU14.Case22 may be referred to as a “plug-in unit housing”.
• FIG. 3 illustrates a detailed view of certain elements ofPIU14 shown inFIGS. 1 and 2, including acase22, alatch40, and apin44.PIU14 may include any plug-in modular unit configured to interface withchassis12 and provide additional and/or supplemental functionality to a communication network (e.g., a printed circuit board with various associated components plugging into a backplace assembly). As shown inFIGS. 1-3,PIU14 may be configured to slide intochassis12 so thatcase22 interfaces with the front edges ofchassis12.Case22 may be made of any appropriate material suitable for use with the communications network (e.g., plastic and/or metal).
• Latch40 may include ahead50, arigid body60, and alever70. In the embodiment shown,head50,rigid body60, andlever70 may be manufactured as a unitary body. Variousdetails regarding latch40 are discussed below in relation toFIGS. 4A-5C.
• Case22 may also define anotch24, ahole46, and aslot48 configured to interface withlatch40 andpin44. As shown inFIG. 3, notch24 may be configured to mount thehead50 oflatch40.Head50 may be configured to rotate withinnotch24 aroundpin44.Pin44 may be any device, component, and/or feature ofcase22 configured to provide a pivot point forlatch40 and/orhead50.Pin44 may include a head, threads, and/or any other features designed for ease of manufacturing, operation, and/or assembly. As shown inFIG. 3, pin44 may pass throughhole46 ofcase22 andhole52 ofhead50.
• Head50 oflatch40 may include atab56 configured to interface with one or more features, devices, and/or components associated with chassis12 (e.g., a slot, a detent, and/or any other appropriate feature). In the embodiment shown,tab56 may be configured to resist the removal ofPIU14 as long astab56,head50, and/or latch40 is engaged withchassis12.
• Rigid body60 may include any portion oflatch40 configured to resist deformation. For example,rigid body60 may include a portion oflatch40 with increased thickness compared to other portions, with ribs and/or other strengthening features, and/or other rigid characteristics. In some embodiments,rigid body60 may provide a handle for a user to actuatelatch40.
• Detent72 oflever70 may be configured to interface withslot48. Whendetent72 is engaged withslot48,head50 andtab56 may not rotate aroundpin44. As long as the rotation ofhead50 andtab56 is restricted,head50 andtab56 will resist the removal ofPIU14 fromchassis12.Lever70 may include any flexible member configured to allow a user to disengagedetent72 fromslot48. As shown inFIG. 3, some embodiments may include alever70 extending fromrigid body60.
• FIGS. 4A and 4B show various views ofexample latch40 for use withPIU14, in accordance with teachings of the present disclosure. In the embodiment shown, latch40 includeshead50,rigid body60, andlever70 all manufactured as a unitary body. Different portions of the body oflatch40 may include varying thicknesses, rigidity, and/or other characteristics as described herein.Manufacturing latch40 as a unitary body may provide several advantages. For example, latch40 may consist of a single material throughout (e.g., metal and/or plastic), reducing assembly steps, manufacturing processes, and/or costs.
• Head50 may be configured to interact with various portions ofPIU14 and/orchassis12.Head50 may include ahole52, aneck54, and atab56.Hole52 may be configured to interface withpin44 and to provide a mount forlatch40 withcase22 ofPIU14.Hole52 may include a simple through-hole, as shown inFIG. 4A. In other embodiments,hole52 may include additional features (e.g., a step, a neck, etc.).Neck54 may include any feature and/or component ofhead50 configured to provide clearance, geometrical, and/or operational advantages. As described in relation toFIG. 3,tab56 may be configured to interact with one or more features of chassis12 (e.g., a strikeplate) to resist removal ofPIU14 fromchassis12. In the embodiment shown,tab56 includes aface58.Face58 may provide a point and/or surface in contact with the one or more features ofchassis12 to transfer force fromlatch40 tochassis12. Various alternative configurations ofhead50 are illustrated inFIGS. 5A-5C.
• Rigid body60 may include any portion oflatch40 configured to resist deformation. For example,rigid body60 may be configured to provide a handle for a user to operatelatch40 as well as to transmit rotational force from the handle to head50 without significant deformation inrigid body60. As shown inFIGS. 4A and 4B,rigid body60 may includewells62 andribs64. Persons having ordinary skill in the art will be able to design and/or select a pattern ofwells62 andribs64 to optimize the balance between weight, material, and resistance to bending and/or other deformation.
• Lever70 may include any portion oflatch40 configured to flex under force applied by a user so as to movedetent72. As discussed above,detent72 may be configured to interface withslot48 ofcase22 and to resist rotation oflatch40 aroundpin44 while detent is engaged withslot48. In the embodiment shown,lever70 includes a y-shaped body with oneleg74 extending fromrigid body60 oflatch40.Leg74 may be configured to provide the required flexibility by adjusting its dimensions (e.g., thickness, length, and/or width). Variation of the thickness ofleg74 may control, at least in part, the travel ofdetent72 during use.
• Lever70 may include acurved handle76 configured to match the shape of a portion ofrigid body60, as shown inFIGS. 4A and 4B.Curved handle76 may define aninterface78 for a user's fingers when he or she actuateslever70. Ifcurved handle76 matches the shape of a portion ofrigid body60, the total travel distance ofcurved handle76 may be limited, which would, in turn, limit the maximum flex or rotational angle applied toleg74 oflever70. Limiting the maximum rotational angle travelled byleg74 may provide additional safety against the plastic deformation ofleg74 and/orlever70 during and/or after repeated use. Because some users may liftPIU14 fromchassis12 usinglatch40 while their fingers are engaged withhandle76, protectingleg74 and/or lever70 from excessive force may be important. In contrast to other latches using spring-loaded locking mechanisms, latches incorporating the teachings of the present disclosure may include fewer parts, greater reliability, and reduced cost of manufacturing.
• As shown inFIGS. 4A and 4B, latch40 incorporating the teachings of the present disclosure may providehead50 andtab56 physically separated fromdetent72. Alatch40 with physically separated features as shown also has the insertion/removal force (e.g.,head50 and/or tab56) applied at a location separated from the locking force (e.g., detent72). Alatch40 with this feature may provide different required forces for insertion/removal and locking. In addition, alatch40 with this feature may allow PIUs andchassis12 with varying faceplate geometries. For example, latch40 may be used with achassis12 in a 2U platform or a 4U platform.Latch40 may also be scaled geometrically to provide increased force in alarger chassis12. In one embodiment, latch40 was tested and provided more than 80 pounds of retention force athead50 while requiring less than 10 pounds to operatelever70.
• Another embodiment oflatch40 manufactured with Makrolon was tested to determine the travel and forces present inlever70. In those tests, it was determined that handle76 oflever70 travelled 3.2 mm when 4.8 pounds of force were applied, resulting in 1.4 mm of travel fordetent72 which was sufficient to disengage withslot48. In the same test, the maximum stress on any part oflever70 was 63 MPa, providing a safety factor of approximately 1.5.
• Another embodiment oflatch40 manufactured with Ultem was tested. In those tests, handle76 oflever70 travelled 3.2 mm when 6.7 pounds of force were applied. The maximum stress induced was 90 MPa, providing a safety factor of approximately 1.5.
• FIGS. 5A-5C show details of various example head configurations for alatch40 for use with plug-inunit14, in accordance with teachings of the present disclosure. Eachexample head50 includes ahole52, aneck54, andtab56 as discussed with relation toFIGS. 4A and 4B. As shown inFIGS. 5A-5C, the configuration ofhead50 may be adjusted to provide various advantages, including maximum retention force. Although the present invention has been described with several embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present invention encompass such changes and modifications as fall within the scope of the appended claims.

Claims (27)

1. A latch for use with a plug-in unit, the latch comprising:

a head configured to retain the plug-in unit within a chassis associated with a rack system;

a rigid body extending from the head configured to interface with a user's fingers;

a pin extending transversely from both sides of the head into a case associated with the plug-in unit, the pin configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers; and

a lever extending from the rigid body, the lever including a detent configured to engage the case;

the detent configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the chassis;

the lever operable to release the detent from the chassis;

wherein the head, the rigid body, the lever, and the detent are manufactured as a single unitary body.

2. A latch according toclaim 1, further comprising the pin manufactured as a separate body and extending through a hole disposed in the head.

3. A latch according toclaim 1, wherein the head further comprises a tab configured to extend within a recess formed in the chassis and configured so that the tab is removed from the recess by the rotation of the head around the pin.

4. A latch according toclaim 1, wherein the rigid body includes a generally planar member.

5. A latch according toclaim 1, wherein the rigid body includes:

a generally planar member; and

ribs extending from the planar member to increase the rigidity of the rigid body;

wherein the rigid body is aligned so that the pin is transverse to the generally planar member.

6. A latch according toclaim 1, wherein the lever includes a y-shaped extension.

7. A latch according toclaim 1, further comprising:

wherein the rigid body includes:

a generally planar member; and

ribs extending from the planar member to increase the rigidity of the rigid body

the lever includes a y-shaped extension having a first leg connected to the rigid body, the first leg flexible in the plane of the generally planar member.

8. A latch according toclaim 1, wherein the detent and the head are physically separated along the body of the latch.

9. A latch according toclaim 1, wherein the single unitary body includes various material thicknesses to maintain rigidity in the rigid body while allowing flexibility in the lever.

10. A case for a plug-in unit for use with a chassis mounted in a rack system, the case comprising:

a housing for the electronic components of the plug-in unit;

a head configured to retain the plug-in unit within the chassis;

a rigid body extending from the head configured to interface with a user's fingers;

a pin extending transversely from both sides of the head into the housing, the pin configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers; and

a lever extending from the rigid body, the lever including a detent configured to engage the case;

the detent configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the chassis;

the lever operable to release the detent from the chassis;

wherein the head, the rigid body, the lever, and the detent are manufactured as a single unitary body.

11. A case according toclaim 10, further comprising the pin manufactured as a separate body and extending through a hole disposed in the head.

12. A case according toclaim 10, wherein the head further comprises a tab configured to extend within a recess formed in the chassis and configured so that the tab is removed from the recess by the rotation of the head around the pin.

13. A case according toclaim 10, wherein the rigid body includes a generally planar member.

14. A case according toclaim 10, wherein the rigid body includes:

a generally planar member; and

ribs extending from the planar member to increase the rigidity of the rigid body;

wherein the rigid body is aligned so that the pin is transverse to the generally planar member.

15. A case according toclaim 10, wherein the lever includes a y-shaped extension.

16. A case according toclaim 10, further comprising:

wherein the rigid body includes:

a generally planar member; and

ribs extending from the planar member to increase the rigidity of the rigid body; and

the lever includes a y-shaped extension having a first leg connected to the rigid body, the first leg flexible in the plane of the generally planar member.

17. A case according toclaim 10, wherein the detent and the head are physically separated along the body of the latch.

18. A case according toclaim 10, wherein the single unitary body includes various material thicknesses to maintain rigidity in the rigid body while allowing flexibility in the lever.

19. A rack system for use with a communications network, the rack system comprising:

two or more vertical posts defining bays for a plurality of chassis;

a chassis mounted to the two or more vertical posts and providing a shelf for a plug-in unit;

a strikeplate associated with the shelf;

a case associated with the electronic components of the plug-in unit;

a head configured to retain the plug-in unit within the chassis by applying a retention force against the strikeplate;

a rigid body extending from the head configured to interface with a user's fingers;

a pin extending transversely from both sides of the head into the housing, the pin configured so that the head and the rigid body rotate around the pin as a single body when the rigid body is pulled by the user's fingers; and

a lever extending from the rigid body, the lever including a detent configured to engage the chassis;

the detent configured to restrict the head and the rigid body from rotating around the pin when the detent is engaged with the case;

the lever operable to release the detent from the chassis;

wherein the head, the rigid body, the lever, and the detent are manufactured as a single unitary body.

20. A rack system according toclaim 19, further comprising the pin manufactured as a separate body and extending through a hole disposed in the head.

21. A rack system according toclaim 19, wherein the head further comprises a tab configured to extend within a recess formed in the chassis and configured so that the tab is removed from the recess by the rotation of the head around the pin.

22. A rack system according toclaim 19, wherein the rigid body includes a generally planar member.

23. A rack system according toclaim 19, wherein the rigid body includes:

a generally planar member; and

ribs extending from the planar member to increase the rigidity of the rigid body;

wherein the rigid body is aligned so that the pin is transverse to the generally planar member.

24. A rack system according toclaim 19, wherein the lever includes a y-shaped extension.

25. A rack system according toclaim 19, further comprising:

wherein the rigid body includes:

a generally planar member; and

ribs extending from the planar member to increase the rigidity of the rigid body; and

the lever includes a y-shaped extension having a first leg connected to the rigid body, the first leg flexible in the plane of the generally planar member.

26. A rack system according toclaim 19, wherein the detent and the head are physically separated along the body of the latch.

27. A rack system according toclaim 19, wherein the single unitary body includes various material thicknesses to maintain rigidity in the rigid body while allowing flexibility in the lever.

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